The tricuspid valve controls blood flow from the right atrium to the right ventricle of the heart, preventing blood from flowing backwards from the right ventricle into the right atrium so that it is instead forced through the pulmonary valve and into the pulmonary arteries for delivery to the lungs. A properly functioning tricuspid valve opens and closes to enable blood flow in one direction. However, in some circumstances the tricuspid valve is unable to close properly, allowing blood to regurgitate back into the atrium. Such regurgitation can result in shortness of breath, fatigue, heart arrhythmias, and even heart failure.
Tricuspid valve regurgitation has several causes. Functional tricuspid valve regurgitation (FTR) is characterized by structurally normal tricuspid valve leaflets that are nevertheless unable to properly coapt with one another to close properly due to other structural deformations of surrounding heart structures. Often, the right ventricle is dilated as a result of pulmonary hypertension or an abnormal heart muscle condition (cardiomyopathy).
Other causes of tricuspid valve regurgitation are related to degenerative valves and/or defects of the tricuspid valve leaflets, tricuspid valve annulus, or other tricuspid valve structures. In some circumstances, tricuspid valve regurgitation is a result of infective endocarditis, blunt chest trauma, rheumatic fever, Marfan syndrome, carcinoid syndrome, improper placement of pacemaker leads, or congenital defects to the structure of the heart.
Tricuspid valve conditions are also often associated with problems related to the left side of the heart, such as mitral valve regurgitation. In particular, FTR is often associated with left heart pathologies, though it is typically left untreated during left heart surgeries. Left heart pathologies such as mitral valve regurgitation and stenosis can induce pressure and volume overload in the right ventricle, which in turn can induce ventricle enlargement and tricuspid annular dilation. Though often relatively mild at the time of treatment of the left heart, this annular dilation of the tricuspid valve is progressive and asymmetric, and FTR becomes more severe as time goes on. Reoperation for repair of the tricuspid valve is often needed owing to the degenerative character of the pathology.
Tricuspid valve regurgitation is often treated by replacing the tricuspid valve with a replacement valve implant. However, valve replacement procedures typically involve drastic measures that remove or render inoperable the natural tricuspid valve tissues. Moreover, some patients are not suitable candidates for a valve replacement procedure. For example, patients having pacemaker leads in the vicinity of the valve cannot easily or safely undergo a valve replacement procedure.
Other treatment options involve repairing the valve through an interventional procedure. However, issues can arise related to deployment and effectiveness of various treatment options. For instance, properly positioning and aligning a repair device with respect to the tricuspid valve can be difficult, particularly considering that the valve leaflets and other structures are continuously moving within the dynamic cardiac environment.
The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one exemplary technology area where some embodiments described herein may be practiced.